Search Excluded post appearing in blog

Hi,

The Shipping & Returns post is appearing in the blog even though it is Search Excluded.
https://bansuribliss.com/blog

I added the following code to Fluent Snippets to fix the issue but it doesn’t work.
What do you suggest?
Thanks!

add_action('pre_get_posts', function ($query) { 
    if (!is_admin() && $query->is_main_query() && $query->is_archive()) { 
        $search_exclude_ids = get_option('sep_exclude'); 
        if ($search_exclude_ids) { 
            $posts_not_in = $query->get('post__not_in', array()); 
            $query->set('post__not_in', array_merge($posts_not_in, $search_exclude_ids)); 
        } 
    } 
});

The page I need help with: [log in to see the link]